How to Use Rotary Cutting Tools

There are three rotary cutting tools on my list of essential sewing tools. In my opinion, the rotary cutter along with a rotary cutting mat and ruler is the way to go if you’re cutting straight edges as well as strips, squares, rectangles, and triangles.

What are the Rotary Cutting Tools?

Rotary Cutters

Rotary cutters come in different shapes and sizes.

A rotary cutter is a cutting tool with a sharp circular blade. The blade rotates around an axle attached to a handle. Because the blade is so sharp, there is a way to expose it when you need it and cover it when it isn’t in use.

Rotary Cutting Mats

Rotary cutting mats come in different sizes and colors.

A rotary cutting mat should always be under the fabric when you’re using a rotary cutter.

The rotary cutting mat is also called a self-healing cutting mat. This tool is made specifically to be used with rotary cutters. The sharp blade cuts into the mat but doesn’t leave any evidence behind that it was there.

Rotary cutting mats have a grid on them along with many other lines that cross and curve through the grid. These lines can be used in a variety of ways to ensure accurate measuring before cutting.

Rotary Cutting Rulers

These are my rotary cutting rulers. There are 10 different rulers of different shapes, sizes, and brands.

Rotary cutting rulers come in different shapes and sizes. They have grid lines along with other lines, too, to assist with accurate measuring.

Buying Rotary Cutting Tools

There are many different companies that make rotary cutting tools. There may be slight variations between manufacturers. I’ve seen it recommended to use the same brand of mat as ruler.

I’ve bought several rotary cutting rulers at garage and estate sales. When I get home, I check to see if the grid lines on the rulers match up exactly with the grid lines on the mats I already have. If they do, I keep them.

My suggestion is if you end up with different brands of rotary cutting mats and rulers, check the grid lines against each other to make sure they line up exactly before using them.

Rotary Cutting Vocabulary

In order to better understand the rotary cutting basics described below, there are a few geometry terms you need to know related to the lines on the rotary cutting mats and rulers.

parallel – lines that are an equal distance apart; they will never intersect or come together

perpendicular – lines that intersect at a right angle

horizontal – lines that go left to right

vertical – lines that go up and down

rightangle – a 90-degree angle

squared – when the cut edge and the top/bottom edge are perpendicular to each
other; the intersection is a 90-degree angle

Applying the Vocabulary

The blue lines are horizontal and parallel to each other.

The red lines are vertical and parallel to each other.

Lines A and B are perpendicular to each other. So are lines BC, CD, and AD.

The red lines can represent a cut edge of fabric. The red lines are perpendicular to the blue lines.

Each corner is a rightangle.

The rectangle can be described as ‘squared‘.

Why I’m Using Felt for the Tutorial

I had several pieces of felt left over from a previous project. They were all originally small sheets of felt approximately 9 x 12 inches when I got them. However, I had cut pieces off for different projects and all the edges were not necessarily straight anymore.

The felt is a solid color and doesn’t have a grain so it’s easier to see how to use the rotary cutting tools.

Rotary Cutting Basics

With all the lines on both the rotary cutting mat and the ruler, it can be a little confusing on exactly what lines you’re supposed to be looking at when using the rotary cutting tools.

One piece of advice that finally made all the lines click in my mind is to use either the lines on the mat or the lines on the ruler but not necessarily both of them at the same time.

Note: My directions are for a right-handed person.

Rotary Cutting Safety

Rotary cutter blades are VERY sharp.

Always cover the blade on the rotary cutter when you aren’t using it. Do not leave the sharp blade exposed when you are not using it.

Always push the rotary cutter away from your body.

Keep rotary cutters out of reach of children and pets.

Using the Lines on the Ruler

Felt doesn’t have a grain line. To make sure it’s square, a horizontal edge needs to be perpendicular to a vertical edge.

To make sure the felt was squared, I lined up the 2-inch horizontal line on the ruler with the bottom edge of the felt. I only paid attention to the lines on the ruler and didn’t use any lines on the mat. (See Photo 1.)

Then I lined up the vertical 5-inch line on the ruler with the left edge of the felt. Both edges of the fabric lined up exactly with the perpendicular lines on the ruler. This means the felt is squared because the bottom left-hand corner of the felt forms a 90-degree angle. (See Photo 1.)

Photo 1

Since the felt was squared and the ruler was placed so there was a 5-inch strip of felt, I was ready to cut the strip. To do this, I held the ruler in place with my left hand. With my right hand holding the rotary cutter, I pressed down firmly and pushed it against the right edge of the ruler rolling the blade along the entire width of the felt.

The next step was to cut the 5-inch strip into squares. In Photo 2 (below) you’ll see the strip I just cut. I rotated the strip so what was the bottom edge of the felt in Photo 1 (above) is the left edge in Photo 2 (below).

I’m now ready to cut it into 5 X 5-inch squares. To do this, I used only used the lines on the ruler again and no lines on the cutting mat. You can see in the photo how I matched up the lines on the ruler with 3 sides of the felt. When I cut the felt along the right edge of the ruler, I had a perfect 5 x 5-inch square.

Photo 2

Use the Lines on the Mat

A few sheets of felt looked a little wonky on more than one side. I could tell they weren’t squared so I couldn’t use the lines on the ruler.

To square up the felt (having 2 perpendicular sides intersect at a 90-degree angle), I used the lines on the mat.

First, I matched the bottom edge of the felt with one of the lines on the cutting mat and laid it down. It was almost a perfect match. (See Photo 3.)

Photo 3

Then, I took the ruler and set it on the felt matching up a horizontal line on the ruler to the line on the mat where the bottom edge of the felt rested. (See Photo 3.)

I slid the ruler over so the right edge of the ruler was lined up with a vertical grid line on the mat close to the edge of the felt. (See Photo 3.)

This grid line is perpendicular to the line on the mat where the bottom edge of the felt is resting. Because these two lines are perpendicular (forming a right angle) where they intersect, the felt will be squared after cutting the felt off the right side of the ruler.

To get the 5 x 5-inch squares, my next steps would be to use the lines on the rulers (as described above with Photo 1) to get a strip that is 5-inches wide. After that, I would cut it into 5 x 5-inch squares (as explained with Photo 2).

Cutting Woven Fabric

Woven fabric has selvages. These are helpful when squaring up fabric before cutting it into strips, squares, rectangles, or triangles.

One way to use the selvages is to line them up while holding the fabric in both hands. With the fabric hanging down, adjust the fabric to the left/right and make sure there isn’t a bubble or ripple in the fabric.

In one motion, gently lay the fabric down on the cutting mat with the selvages close to you. Then carefully fold the fabric in half matching the selvages with the fold. Smooth the fabric and line up the folded edge of the fabric with a horizontal line on the cutting mat.

Now you can either use the lines on the ruler or the lines on the mat to place the ruler in position to cut a straight edge with the rotary cutter.

The lines on the mat are being used to place the ruler in position before cutting.

Another way to use the selvage for squaring the fabric is if you only have one selvage on the fabric. (The other one was cut off.)

Fold the fabric in half so the selvages are matched up. Depending on the size of the fabric, you can fold it again keeping the selvages lined up. This edge is a straight edge.

Now you can lay one of the ruler’s horizontal lines on the fold or you can place the fold on a horizontal line on the cutting mat. Either way (using the lines on the ruler or the lines on the mat) will result in a straight cut.

A horizontal line on the ruler was placed on the fold of the fabric. This means a cut along the right edge of the ruler will square up the fabric.

Rotary Cutting Tips

My number one tip for rotary cutting is either use the lines on the ruler or the lines on the mat to get the straight edge you need for cutting.

In addition, there are several other tips for using rotary cutting tools.

If you are right-handed, the ruler should be to the left of where you want to cut.

Place your pinky on the rotary cutting mat while holding the ruler down firmly with your thumb and other fingers. This will help the ruler from shifting while you’re cutting.

Make sure the blade of the rotary cutter is right up against the edge of the ruler.

Press firmly on the rotary cutter as you push it across the fabric. A sharp blade will cut through it without a problem. If you get sections where the fabric isn’t cut, the blade may need to be changed.

Rotary Cutter Safety (Again)

Because rotary cutter blades are VERY sharp, I want to emphasize safety.

Always cover the blade on the rotary cutter when you aren’t using it. Do not leave the sharp blade exposed between cuts while it is sitting on the mat.

Hello, I'm Nicki!

Having a creative outlet is a necessity. My goal is to educate and inspire others in sewing-related projects that are fun, functional, or both. Sign up to receive notice when new posts have been published.

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Hello, I’m Nicki!

Welcome to The Ruffled Purse! If you've been wanting to learn how to sew or already know how to sew but want to spend more time doing it, you're in the right place. Here you'll find education and inspiration for sewing projects for yourself, your home, and others. About me...